Field of the Invention
This disclosure relates generally to sorption refrigeration systems using sorbers and with complex compounds and a sorber gas that are configured to provide rapid cooling features. In particular, features for a rapid pulldown of a thermal load, for example for flash freezing or cooling a fast-rising heat load.
Description of the Related Art
Adsorption/desorption or also referred to as absorption/desorption reactions between polar gases and certain metal salts yield complex compounds which are the basis for efficient refrigeration, thermal storage, heat pump systems and power systems having high energy density. However, energy density, a measure of the quantity of polar gas adsorbed on the salt, which translates into the amount of work or energy which can be stored in a given amount of the complex compound, is only one parameter to be considered in designing commercially attractive systems.
Of significance, if not greater importance, are the reaction rates between the gas and the complex compound, which result in the time it takes to adsorb and desorb a given amount of the gas into or from the complex compound. Increased or maximized reaction rates result in increased or improved power that can be delivered by the system, i.e., more energy delivered over a period of time, which translates into a greater heating, cooling or power capability of the system.
The reaction rates in these systems are partly a function of how efficiently the gas is distributed to the complex compound. Previous systems have used porous ceramics or cloth to distribute gas to the complex compound. However, the ceramic distributors are fragile and can fracture easily, especially in non-stationary or vibratory environments. For example, ceramic distributors can have difficulty withstanding the vibrations caused by transportation in rough terrain. Cloth distributors have also been found to have some downsides, particularly due to their propensity to clog after multiple cycles. This clogging can increase the pressure drop of the refrigerant in the systems and thereby reduce the performance of the sorber and the absorption system.